The average marks of 50 students in an examination was 65. It was later found that the marks of one student had been wrongly entered as 83 instead of 38. The correct average is ?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 ie 64.1
Sum of scores of all students = 50 × 65 = 3250
After adding and substracting correct and wrong value,
= 3250 + 38 - 83
= 3205
Corrected average = 3205/50 = 64.1